Current research in physiology最新文献

{"title":"Biochemical properties of H+-Ca2+-exchanger in the myometrium mitochondria","authors":"Yurii V. Danylovych,&nbsp;Hanna V. Danylovych,&nbsp;Oksana V. Kolomiets,&nbsp;Marina D. Sviatnenko,&nbsp;Sergiy O. Kosterin","doi":"10.1016/j.crphys.2022.09.005","DOIUrl":"10.1016/j.crphys.2022.09.005","url":null,"abstract":"<div><p>Some biochemical properties of the H⁺-Ca²⁺-exchanger in uterine smooth muscle mitochondria have been described. The experiments were performed on a suspension of isolated mitochondria from the myometrium of rats. Methods of confocal microscopy, spectrofluorimetry and photon correlation spectroscopy were used. Fluo-4 probe was used to record changes in ionized Ca²⁺ in the matrix and cytosol; pH changes in the matrix were evaluated with BCECF. It was experimentally proved that in the myometrium instead of Na⁺-Ca²⁺-exchanger the H⁺-Ca²⁺-exchanger functions. It was activated at a physiological pH value, was carried out in stoichiometry 1: 1 and was electrogenic. The transport system was modulated by magnesium ions and the diuretic amiloride, but was not sensitive to changes in the concentration of extra-mitochondrial potassium ions. H⁺-Ca²⁺-exchanger was suppressed by antibodies against the LETM1 protein. Calmodulin may act as a regulator of H⁺-Ca²⁺-exchanger by inhibiting it.</p></div>","PeriodicalId":72753,"journal":{"name":"Current research in physiology","volume":"5 ","pages":"Pages 369-380"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/c4/cd/main.PMC9513619.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40385187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of carbohydrate-electrolyte dissolved alkaline electrolyzed water on physiological responses during exercise under heat stress in physically active men","authors":"Shohei Dobashi ,&nbsp;Tomohiro Kobayashi ,&nbsp;Yoshinori Tanaka ,&nbsp;Yudai Shibayama ,&nbsp;Katsuhiro Koyama","doi":"10.1016/j.crphys.2022.09.007","DOIUrl":"10.1016/j.crphys.2022.09.007","url":null,"abstract":"<div><h3>Purpose</h3><p>This study investigated the effects of 1400 mL intake of alkaline electrolyzed water (AEW) or purified water (PW) into which carbohydrate-electrolyte (CE) was dissolved on improving physiological responses during exercise under heat stress.</p></div><div><h3>Methods</h3><p>This double-blinded, crossover randomized controlled trial included 10 male participants who completed two exercise trials in a hot environment (35 °C, ambient temperature, and 50% relative humidity) after consuming CE-dissolved PW (P-CE) or CE-dissolved AEW (A-CE). The exercise trial consisted of running for 30 min on a treadmill (at an intensity corresponding to 65% of heart rate reserve adjusted for heat stress conditions) and repeated sprint cycling (10 × 7-s maximal sprint cycling), with a 35-min rest interval between the two exercises, followed by a 30-min post-exercise recovery period. Before and after running, and after cycling, the participants drank P-CE (hydrogen concentration of 0 ppm, pH 3.8) or A-CE (0.3 ppm, pH 4.1). Blood samples were obtained before, during (rest interval between running and cycling), and post-exercise.</p></div><div><h3>Results</h3><p>Repeated sprint performance and oxidative stress response did not differ between the P-CE and A-CE trials. A-CE consumption significantly attenuated the increase in blood lactate concentration during the running exercise but not during repeated sprint cycling under heat stress conditions.</p></div><div><h3>Conclusion</h3><p>Our findings suggested that A-CE did not significantly affect repeated sprint performance; however, the attenuated elevation in blood lactate by A-CE ingestion implies a partial enhancement of endurance performance during submaximal exercise under heat stress.</p></div>","PeriodicalId":72753,"journal":{"name":"Current research in physiology","volume":"5 ","pages":"Pages 389-398"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/9f/b2/main.PMC9525732.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"33487209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Shaping the cardiac response to hypoxia: NO and its partners in teleost fish","authors":"Sandra Imbrogno ,&nbsp;Tiziano Verri ,&nbsp;Mariacristina Filice ,&nbsp;Amilcare Barca ,&nbsp;Roberta Schiavone ,&nbsp;Alfonsina Gattuso ,&nbsp;Maria Carmela Cerra","doi":"10.1016/j.crphys.2022.03.006","DOIUrl":"10.1016/j.crphys.2022.03.006","url":null,"abstract":"<div><p>The reduced availability of dissolved oxygen is a common stressor in aquatic habitats that affects the ability of the heart to ensure tissue oxygen supply. Among key signalling molecules activated during cardiac hypoxic stress, nitric oxide (NO) has emerged as a central player involved in the related adaptive responses. Here, we outline the role of the nitrergic control in modulating tolerance and adaptation of teleost heart to hypoxia, as well as major molecular players that participate in the complex NO network. The purpose is to provide a framework in which to depict how the heart deals with limitations in oxygen supply. In this perspective, defining the relational interplay between the multiple (sets of) proteins that, due to the gene duplication events that occurred during the teleost fish evolutive radiation, do operate in parallel with similar functions in the (different) heart (districts) and other body districts under low levels of oxygen supply, represents a next goal of the comparative research in teleost fish cardiac physiology.</p></div>","PeriodicalId":72753,"journal":{"name":"Current research in physiology","volume":"5 ","pages":"Pages 193-202"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2665944122000189/pdfft?md5=e85c0654a32aada6bde0c0b1ef544f60&pid=1-s2.0-S2665944122000189-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44451941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A sudden change of heart: Warm acclimation can produce a rapid adjustment of maximum heart rate and cardiac thermal sensitivity in rainbow trout","authors":"Matthew J.H. Gilbert ,&nbsp;Olivia A. Adams ,&nbsp;Anthony P. Farrell","doi":"10.1016/j.crphys.2022.03.003","DOIUrl":"10.1016/j.crphys.2022.03.003","url":null,"abstract":"<div><p>Warm acclimation in fish is often characterized by an increase in heat tolerance and a reduction in physiological rates to improve the scope to respond to additional challenges including further warming. The speed of these responses can determine their effectiveness. However, acclimation rates vary across levels of biological organization and are poorly understood in part because most research is conducted after an acclimation period of &gt;3 weeks, when acclimation is presumed to be complete. Here we show that when rainbow trout were transferred from 10 to 18 °C, over 50% of the total reduction of maximum heart rate (ƒ_Hmax) (i.e. the thermal compensation at moderate temperatures) occurred within 72 h, with further compensation occurring more gradually over the following 25 days. Also, the ability to increase ƒ_Hmax with acute warming improved within 24 h resulting in a 30% rise in peak ƒ_Hmax, but this ultimately declined again with prolonged (28 days) exposure to 18 °C. In contrast with some previous studies, upper critical temperatures for ƒ_Hmax did not increase. Nonetheless, we demonstrate that rapid cardiac plasticity is possible in rainbow trout and likely blunts the impacts of thermal variation over relatively short timescales, such as that associated with heat waves and migration between water bodies.</p></div>","PeriodicalId":72753,"journal":{"name":"Current research in physiology","volume":"5 ","pages":"Pages 179-183"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2665944122000153/pdfft?md5=ab7e1bbd47e781464a2696304389478b&pid=1-s2.0-S2665944122000153-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41900514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Region-specific effects of antenatal/early postnatal hypothyroidism on endothelial NO-pathway activity in systemic circulation","authors":"Dina K. Gaynullina ,&nbsp;Svetlana I. Sofronova ,&nbsp;Ekaterina K. Selivanova ,&nbsp;Anastasia A. Shvetsova ,&nbsp;Anna A. Borzykh ,&nbsp;Olga S. Tarasova","doi":"10.1016/j.crphys.2021.12.002","DOIUrl":"10.1016/j.crphys.2021.12.002","url":null,"abstract":"<div><h3>Background</h3><p>Antenatal/early postnatal hypothyroidism weakens NO-mediated anticontractile influence of endothelium in coronary arteries of adult rats, but it remains unclear whether this occurs in other vascular regions. We hypothesized that developmental thyroid deficiency is followed by region-specific changes in the endothelial NO-pathway activity in systemic vasculature. To explore this, we estimated the effects of antenatal/early postnatal hypothyroidism on NO-pathway activity and its potential local control mechanisms in rat mesenteric and skeletal muscle (sural) arteries.</p></div><div><h3>Methods</h3><p>Dams were treated with 6-propyl-2-thiouracil (PTU) in drinking water (0.0007%) during pregnancy and 2 weeks postpartum; control (CON) females received PTU-free water. Adult offspring (10–12-weeks) arteries were studied by wire myography, qPCR, and Western blotting.</p></div><div><h3>Results</h3><p>Endothelium removal or inhibition of NO-synthase with L-NNA augmented contractile responses to α₁-adrenoceptor agonist methoxamine. In PTU compared to CON group, these effects were stronger in sural arteries, but did not differ in mesenteric arteries. The responses of both arteries to NO-donor DEA/NO were similar in CON and PTU rats. mRNA contents of deiodinase 2 and thyroid hormone receptor α were similar in mesenteric arteries of two groups but were elevated in sural arteries of PTU group compared to CON. The abundance of eNOS protein was higher in sural arteries of PTU compared to CON rats.</p></div><div><h3>Conclusion</h3><p>Antenatal/early postnatal hypothyroidism is followed by an increase in NO-mediated anticontractile influence in sural, but not in mesenteric arteries of adult animals. The diversity of hypothyroidism effects may be due to different alterations of local T3 synthesis/reception in different vascular beds.</p></div>","PeriodicalId":72753,"journal":{"name":"Current research in physiology","volume":"5 ","pages":"Pages 8-15"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/89/65/main.PMC8692882.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39785631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Respiratory and thoracoabdominal motion pattern at rest and after sub-maximum effort in children with asthma","authors":"Carla L.F. Cavassini ,&nbsp;Evelim L.F.D. Gomes ,&nbsp;Josiane G. Luiz ,&nbsp;Maisi C.M. David ,&nbsp;Dirceu Costa","doi":"10.1016/j.crphys.2022.06.005","DOIUrl":"10.1016/j.crphys.2022.06.005","url":null,"abstract":"<div><p>Asthma involves an increase in airway resistance even in periods between attacks, which generates changes in thoracoabdominal kinematics. The aim of the present study was to detect these adaptations at rest and after physical effort. Evaluations were performed using optoelectronic plethysmography at rest and immediately after physical effort of moderate intensity. Thirty-two children and adolescents participated in the present study (16 asthma- AG and 16 health controls-CG). After exercise, the AG exhibited a less variability of respiratory variables. The kinematic behavior of thoracoabdominal motion was the inverse of that found in healthy controls. These findings suggest mechanical and physiological adaptations to minimize the possible turbulence of the airflow and reduce the impact of airway resistance during physical exertion. Moreover, these changes are found even at rest and in patients whose asthma is clinically controlled.</p></div>","PeriodicalId":72753,"journal":{"name":"Current research in physiology","volume":"5 ","pages":"Pages 287-291"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/79/9a/main.PMC9254261.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40480547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diet-induced obese mice are resistant to improvements in cardiac function resulting from short-term adropin treatment","authors":"Dharendra Thapa ,&nbsp;Bingxian Xie ,&nbsp;Bellina A.S. Mushala ,&nbsp;Manling Zhang ,&nbsp;Janet R. Manning ,&nbsp;Paramesha Bugga ,&nbsp;Michael W. Stoner ,&nbsp;Michael J. Jurczak ,&nbsp;Iain Scott","doi":"10.1016/j.crphys.2022.01.005","DOIUrl":"10.1016/j.crphys.2022.01.005","url":null,"abstract":"<div><p>Previous studies have shown that treatment with recombinant adropin, a circulating peptide secreted by the liver and brain, restores glucose utilization in the hearts of diet-induced obese mice. This restoration of fuel substrate flexibility, which is lost in obese and diabetic animals, has the potential to improve contractile function in the diabetic heart. Using an <em>ex vivo</em> approach, we examined whether short-term adropin treatment could enhance cardiac function in a mouse model of diet-induced obesity. Our study showed that acute adropin treatment reduces inhibitory phosphorylation of pyruvate dehydrogenase in primary neonatal cardiomyocytes, and leads to moderate improvements in <em>ex vivo</em> cardiac function in mice fed a low fat diet. Conversely, short-term exposure to adropin led to a small decrease in cardiac function in mice fed a long-term high fat diet. Insulin treatment did not significantly alter cardiac function in adropin treated hearts from either low or high fat diet mice, however acute adropin treatment did moderately restore some aspects of downstream insulin signaling in high fat diet fed mice. Overall, these data suggest that in an <em>ex vivo</em> setting, acute adropin treatment alone is not sufficient to promote improved cardiac function in obese animals.</p></div>","PeriodicalId":72753,"journal":{"name":"Current research in physiology","volume":"5 ","pages":"Pages 55-62"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/7a/32/main.PMC8803554.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39895488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seasonal changes of electrophysiological heterogeneities in the rainbow trout ventricular myocardium","authors":"Marina A. Vaykshnorayte ,&nbsp;Vladimir A. Vityazev ,&nbsp;Jan E. Azarov","doi":"10.1016/j.crphys.2022.02.001","DOIUrl":"10.1016/j.crphys.2022.02.001","url":null,"abstract":"<div><h3>Introduction</h3><p>Thermal adaptation in fish is accompanied by morphological and electrophysiological changes in the myocardium. Little is known regarding seasonal changes of spatiotemporal organization of ventricular excitation and repolarization processes. We aimed to evaluate transmural and apicobasal heterogeneity of depolarization and repolarization characteristics in the rainbow trout in-situ ventricular myocardium in summer and winter conditions.</p></div><div><h3>Methods</h3><p>The experiments were done in summer-acclimatized (SA, 18°C, n = 8) and winter-acclimatized (WA, 3°C, n = 8) rainbow trout (<em>Oncorhynchus mykiss</em>). 24 unipolar electrograms were recorded with 3 plunge needle electrodes (eight lead terminals each) impaled into the ventricular wall. Activation time (AT), end of repolarization time (RT), and activation-repolarization interval (ARI, a surrogate for action potential duration) were determined as dV/dt min during QRS-complex, dV/dt max during T-wave, and RT-AT difference, respectively.</p></div><div><h3>Results</h3><p>The SA fish demonstrated relatively flat apicobasal and transmural AT and ARI profiles. In the WA animals, ATs and ARIs were longer as compared to SA animals (p≤0.001), ARIs were shorter in the compact layer than in the spongy layer (p≤0.050), and within the compact layer, the apical region had shorter ATs and longer ARIs as compared to the basal region (p≤0.050). In multiple linear regression analysis, ARI duration was associated with RR-interval and AT in SA and WA animals. The WA animals additionally demonstrated an independent association of ARIs with spatial localization across the ventricle.</p></div><div><h3>Conclusion</h3><p>Cold conditions led to the spatial redistribution of repolarization durations in the rainbow trout ventricle and the formation of repolarization gradients typically observed in mammalian myocardium.</p></div>","PeriodicalId":72753,"journal":{"name":"Current research in physiology","volume":"5 ","pages":"Pages 93-98"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/9a/97/main.PMC8844795.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39949032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modulatory roles of melatonin on respiratory and heart rates and their circadian rhythmicity in donkeys (Equus asinus) subjected to packing during the hot-dry season","authors":"Joseph Olusegun Ayo,&nbsp;Ayodele Stephen Ake","doi":"10.1016/j.crphys.2022.09.002","DOIUrl":"10.1016/j.crphys.2022.09.002","url":null,"abstract":"<div><p>In mammals a central circadian clock is located in the suprachiasmatic nuclei of the hypothalamus, which regulates the innate physiological rhythms to the ambient 24-h light-dark cycle. Melatonin is an essential component of circadian rhythm. The study aimed to evaluate the effects of melatonin administration on the respiratory rate (RR) and heart rate (HR) and their circadian rhythmicity in donkeys subjected to packing (load carrying) during the hot-dry season. Twenty healthy pack donkeys, aged 2–3 years with average weight of 93 ± 2.7 kg were divided into two groups randomly for the experiment. Group 1 donkeys (packing with melatonin) were administered melatonin for seven days during the study and subjected to packing, while group 2 were packed without melatonin administration. Both groups of donkeys were packed three times within the week, one day apart, covering a total distance of 20 km on each experimental day. Meteorological parameters were recorded during the study period. RR and HR were measured pre- and immediately (15 min) post-packing. Continuous measurement of the parameters started 16 h later, after the last packing procedures for a period of 27 h at intervals of 3 h. Temperature-humidity index (THI) pre-packing (73.67 ± 0.7) was lower (P &lt; 0.05) than that obtained post-packing (80.33 ± 1.2). The THI recorded during the continuous measurement was at its peak at 15:00 h (86), indicating that the afternoon hours were thermally stressful to the donkeys. The THI was strongly correlated with HR recorded in packing (without melatonin) compared to packing (with melatonin) donkeys. The RR and HR values in both groups of donkeys were significantly (P &lt; 0.05) higher immediately after packing. However, the post-packing values of the parameters were not different (P &gt; 0.05) between the two groups of donkeys. The mesor (adjusted arithmetic mean) and amplitude of RR and HR in packing (without melatonin) donkeys were significantly (P &lt; 0.05) higher than that recorded in packing (with melatonin) donkeys. In conclusion, melatonin reduced negative influence on the circadian rhythmicity (mesor and amplitude) of RR and HR in donkeys by exerting its anti-stress and antioxidant effects. The study has demonstrated the beneficial effect of melatonin and its administration may mitigate excessive respiratory and cardiac activities that may reduce the work output of donkeys during the hot-dry season.</p></div>","PeriodicalId":72753,"journal":{"name":"Current research in physiology","volume":"5 ","pages":"Pages 381-388"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/14/7d/main.PMC9519433.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40389018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of the sex steroids mediated modulation of leucocyte immune responses in an ophidian Natrix piscator","authors":"Alka Singh,&nbsp;Ramesh Singh,&nbsp;Manish Kumar Tripathi","doi":"10.1016/j.crphys.2022.09.003","DOIUrl":"10.1016/j.crphys.2022.09.003","url":null,"abstract":"<div><p>The immune-suppressive role of sex steroids in mammals is well documented, but information on other vertebrates is limited. The present study was planned to analyze the effect of testosterone and progesterone in the modulation of immune functions of leucocytes in a reptile, <em>Natrix piscator</em>. Reptiles are unique organisms and this study is novel in that it provides an insight into immune-reproductive cross-talk in a reptile. Leucocytes were isolated from peripheral blood, cultured with different concentrations of testosterone and progesterone and different immune parameters like phagocytosis, superoxide production, and nitrite release were assessed. Lymphocytes were isolated and cell-mediated immunity was assessed through proliferation responses utilizing tetrazolium salt. Concentration-dependent suppressive effects of both the steroids on immune responses were observed. A differential suppressive effect of testosterone was also observed when a lymphocyte proliferation assay was studied. Using receptor antagonists such as cyproterone acetate and mifepristone restored the immune responses of cultured cells. It was summarized that gonadal steroids mediate a direct suppressive effect on innate and cell-mediated immune responses of blood immune cells. It was concluded that when gonadal steroids are high in reproductive seasons, the immune functions are suppressed to gain optimum reproductive success.</p></div>","PeriodicalId":72753,"journal":{"name":"Current research in physiology","volume":"5 ","pages":"Pages 355-360"},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/bf/6f/main.PMC9519393.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40389019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}